Cathie Wood is the all-star stock picker in charge of the funds at ARK Invest, and she's a favorite among fans of high-growth stocks. Wood divides her funds into specific market verticals like disruptive innovation, space exploration, next-generation internet, and cryptocurrency.

She's unusual among tech funds in that ARK doesn't shy away from the biotech sector. She has a fund that is focused on the genomics revolution. These three Motley Fool contributors checked out her holdings, and found three investments that they love. Here's why they are bullish on Fate Therapeutics (FATE -3.26%)Veracyte (VCYT -1.96%) and Adaptive Biotechnologies (ADPT -0.78%)

A novel cell therapy play

George Budwell (Fate Therapeutics): Cell therapy has proved to be an important new modality for a host of liquid tumors. But several key problems are still inhibiting the growth of this groundbreaking tech.

First, the current generation of cancer cell therapies requires patients to travel to specialized clinics to have their T-cells harvested, genetically modified, and subsequently reinfused into their bodies. Second, these therapies frequently come with a battery of serious safety concerns. Third, the first batch of approved cell therapies are enormously expensive. And fourth, these first-gen cell therapies aren't particularly effective in the solid-tumor setting. 

Multiple next-generation cell therapy companies are trying to solve these various issues. Fate Therapeutics is one candidate that has caught the eye of Cathie Woods. ARK Invest started buying shares of the novel cell therapy company in 2019 and has since ramped up its position in a significant way.

The company's core-value proposition centers around the idea that its genetically modified induced pluripotent stem therapy platform -- which uses natural killer cells instead of T-cells -- will offer cancer patients a so-called "off the shelf" option, which in theory would be more convenient, less costly, and applicable to a wider array of malignancies (including solid tumors). Fate is a leader in this type of therapy, and its platform is presently in early-stage testing. But pivotal-stage trials for relapsed/refractory aggressive lymphomas are in the planning stages.   

Should retail investors own this high-tech cancer play? If Fate's platform pans out, its shares will undoubtedly soar. Its various target markets are worth tens of billions of dollars in future revenue.

But this biotech stock is the epitome of high-risk, high-reward. There is no guarantee that Fate will crack the code on off-the-shelf cell therapies for cancer. What's more, there are plenty of other cell therapy companies working on this exact same problem.  

A steadily growing niche diagnostics company

Patrick Bafuma (Veracyte): Thinking toward the future, diagnostics company Veracyte already has a handful of products on the market, making it less risky than your average clinical-stage biotech. And business is chugging along, too, with Veracyte recently increasing full-year revenue expectations. The company is guiding for respectable 24% to 28% year-over-year revenue growth after increasing its full-year forecast from a range of $265 million to $275 million, to a range of $272 million to $280 million.

The company's strategy of targeting ambiguous medical decision points has served it well. For example, its Decipher prostate test can help determine whether to watch and wait or to proceed with earlier and more-intensive treatment after surgery for prostate cancer.

Another example of such testing is its Afirma test, which can stratify thyroid nodules for cancer risk after previously inconclusive or indeterminate biopsy results.

This targeted approach has helped Veracyte deliver revenue growth at a 31% compound annual rate since 2018. And despite being down over 60% from its February 2021 highs, the stock is crushing the market since 2017. Investors have enjoyed a 221% gain, more than tripling the 72% gain from the S&P 500 over the last five years.

While its current offerings have room to grow in their respective markets, the company also has several tests in development. Of note, this $1.8 billion med tech is looking to tackle lung cancer next. When a patient is found to have a lung nodule (and 1.6 million nodules are found in the U.S. each year), the next steps can range from monitoring by way of CT scans, biopsies, or other surgical intervention.

Veracyte is looking to make things much easier for patients by only having to use a nasal swab as the next step rather than time-consuming, costly, and potentially unnecessary invasive procedures. While its Percepta swab is still in development, this could eventually become an annual opportunity worth $1 billion or more.

Already experienced in building a market from the ground up, Veracyte has done well so far with a calculated strategy. With a bevy of potential future offerings, including the Percepta nasal swab, growth investors might want to consider giving this diagnostics company a second look.

Adaptive Bio takes a new route toward profitability

Taylor Carmichael (Adaptive Biotechnologies): One of the dangers of biotech investing is that you can fall in love with amazing science and fail to focus on how you will make money. Adaptive isn't profitable yet, but its business is definitely starting to take shape. 

The company has two main business lines right now, Immune Medicine and MRD (minimal residual disease). In the second quarter, the company reported that 51% of its business came from Immune Medicine, and 49% from MRD.

MRD is the gold standard in cancer diagnostics. One of the embarrassing things for an oncology doctor is telling patients that they are in "complete remission" (CR) and then the cancer comes back. The reason the cancer comes back is because there are cancer cells in the patient's body that the CR test misses. MRD is designed to catch all cancers, even the ones you can't see under a microscope. 

Adaptive has the first (and only) MRD test that is Medicare approved. So this is a major winner for the company. MRD is a more specific and more accurate diagnosis of cancer status.

On the Immune Medicine side, CEO Chad Robins made a business decision about its T-Detect program. The ultimate plan for T-Detect is for the diagnostic to reveal multiple indications -- not just cancer, but things like COVID-19. That's an astounding idea: that one day, a doctor can run a simple test and take a look at everything your immune system is fighting.

In the near term, that dream has been put on hold. It would be very expensive trying to get the Food and Drug Administration to approve the T-Detect test, indication by indication. Instead, the biotech elected to hold off on that for now while it builds up more and more data on the test.

Instead, Adaptive's near-term focus is going to prioritize partnering with big pharma. Those revenue numbers are growing by 100% year over year, and it's a higher-margin business. I applaud this. The Adaptive conference call made me as excited as I've ever been about this company.